NSPredicate acting strange in NSFetchedResultsController

Posted by Scott Langendyk on Stack Overflow See other posts from Stack Overflow or by Scott Langendyk
Published on 2010-04-05T20:08:08Z Indexed on 2010/04/05 20:13 UTC
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Filed under:

nsfetchedresultscontrolle

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nspredicate

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iphone

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iphone-sdk

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core-data

I feel as if this should be very simple, but it's behaving strangely.

I have 3 entities, with a relationship as such

Entity A <-->> Entity B <<--> Entity C

I have an NSFetchedResults controller and I'm trying to filter the results of Entity A using the following predicate.

[NSPredicate predicateWithFormat:@"NONE entityB.entityC == %@", self.entityC];

When I try and run the app, the output shows no results. I can alter the predicate slightly to:

[NSPredicate predicateWithFormat:@"ANY entityB.entityC == %@", self.entityC];

And it shows me only the results that I want it to filter out.

Why is this happening?

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